> For the complete documentation index, see [llms.txt](https://docs.onum.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.onum.com/pipelines/actions/transformation/field-transformation/field-transformation-operations/utils/trim-prefix-from-string.md).

# Trim prefix from string

## Description

This operation removes a specified prefix from the beginning of a string, if it exists.

This operation is useful for cleaning or normalizing text data by stripping a known or unwanted prefix from input strings.

***

## Data types

These are the input/output expected data types for this operation:

### Input data

`String` - Strings to be trimmed.

### Output data

`String` - The resulting string after removing the specified prefix.

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## Parameters

These are the parameters you need to configure to use this operation (mandatory parameters are marked with a <mark style="color:red;">**\***</mark>):

<details>

<summary>Prefix to trim<mark style="color:red;"><strong>*</strong></mark></summary>

The prefix to remove from the beginning of the input strings. If the input string starts with this prefix, it will be removed; otherwise, the string will remain unchanged.

</details>

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## Example

Suppose you want to **trim** your input strings by removing a specific **prefix**:

1. In your Pipeline, open the required [Action](/pipelines/actions.md) configuration and select the input **Field**.
2. In the **Operation** field, choose **Trim prefix from string**.
3. Set **Prefix to trim** to `Hello,` .
4. Give your **Output field** a name and click **Save**. The input strings will be trimmed, removing the specified prefix.

For example:

{% code overflow="wrap" %}

```
"Hello, World!" -> "World!"
```

{% endcode %}

{% hint style="info" %}
You can try out operations with specific values using the **Input** field above the operation. You can enter the value in the example above and check the result in the **Output** field.
{% endhint %}